using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using Microsoft.Xna.Framework;
using Microsoft.Xna.Framework.Content;
using Microsoft.Xna.Framework.Graphics;
using Microsoft.Xna.Framework.Input;

namespace CarFire
{
    class GameLogic
    {
        
        Game mGame;
        public GameLogic(Game game)
        {
            mGame = game;
        }
        /// <summary>
        /// Update the game logic.
        /// </summary>
        /// <param name="timespan">timeslice</param>
        /// <param name="thisPlayer">index of the player to center the screen around</param>
        public void Update(TimeSpan timespan, int thisPlayer)
        {
            //Handle projectiles - update and check for wall collisions
            for (int i = 0; i < mGame.State.mProjectiles.Count; i++)
            {
                bool removed = false;
                //Check to see if there are any entities in the square with the projectile
                if (!mGame.IsCellOpen(new Point(mGame.State.mProjectiles[i].Coordinates.X, mGame.State.mProjectiles[i].Coordinates.Y)))
                {
                    //The projectile has hit something.
                    IEntity hitEntity = mGame.GetEntityAtCoordinates(new Point(mGame.State.mProjectiles[i].Coordinates.X, mGame.State.mProjectiles[i].Coordinates.Y));
                    //If it is a monster than decrement monster health and increment the score of the player who shot it.
                    if (hitEntity is IMonster)
                    {
                        IMonster hitMonster = (IMonster)hitEntity;
                        hitMonster.causeDamageTo(mGame.State.mProjectiles[i].Damage);
                        if (hitMonster.Health > 0)
                        {
                            mGame.State.mCharacters[mGame.State.mProjectiles[i].CharacterIndex].Score += mGame.State.HitMonsterScore;
                            Console.WriteLine(mGame.State.mCharacters[mGame.State.mProjectiles[i].CharacterIndex].Score);
                        }
                        else
                        {
                            mGame.State.mCharacters[mGame.State.mProjectiles[i].CharacterIndex].Score += mGame.State.KillMonsterScore;
                            Console.WriteLine(mGame.State.mCharacters[mGame.State.mProjectiles[i].CharacterIndex].Score);
                            //Remove dead monsters
                            mGame.State.Entities.Remove(hitEntity);
                        }
                    }
                    mGame.State.mProjectiles.RemoveAt(i);
                    removed = true;
                    i--;
                }
                if (!removed)
                    mGame.State.mProjectiles[i].Update(timespan);

            }
            //Check for collisons
            for (int j = 0; j < mGame.State.mCharacters.Length; j++)
            {

                if (mGame.State.mCharacters[j] != null)
                    for (int i = 0; i < mGame.State.mProjectiles.Count; i++)
                    {
                        if (mGame.State.mProjectiles[i].Coordinates.X == mGame.State.mCharacters[j].Coordinates.X && mGame.State.mProjectiles[i].Coordinates.Y == mGame.State.mCharacters[j].Coordinates.Y)
                        {
                            mGame.State.mCharacters[j].causeDamageTo(mGame.State.mProjectiles[i].Damage);
                            Console.WriteLine(mGame.State.mCharacters[j].Health);
                            mGame.State.mProjectiles.RemoveAt(i);
                            i--;
                        }
                    }
            }
            //Update input for each player
            for (int i = 0; i < mGame.State.NumberOfPlayers; i++)
            {
                if(mGame.State.mCharacters[i] != null)
                    mGame.State.mCharacters[i].Update(timespan, mGame.State.GetKeysDown(i));
            }
            if (mGame.State.mCharacters[thisPlayer] != null)
            {
                mGame.State.Map.CenterCell = mGame.State.mCharacters[thisPlayer].Position;
            }
            //Handle wall collisions of projectiles again...
            for (int i = 0; i < mGame.State.mProjectiles.Count; i++)
            {
                if (!mGame.State.Map.IsCellOpen(new Point(mGame.State.mProjectiles[i].Coordinates.X, mGame.State.mProjectiles[i].Coordinates.Y)))
                {
                    mGame.State.mProjectiles.RemoveAt(i);
                    i--;
                }

            }
        }
    }
}